The present invention relates to an image processing apparatus and method, and more particularly, to an image processing apparatus and method, which store image data in an image memory.
In recent years, the image quality and functions of digital copying machines have improved, and user's demands have been met in terms of color tones of an output image and its edit processing. In this situation, in order to obtain a desired output image, copying machines having a so-called preview function, which allows a user to confirm an image displayed on, e.g., a CRT in place of repetitively outputting an image onto a recording paper sheet, have become commercially available. In some of these machines, a read original image is displayed and confirmed using a monochrome liquid crystal display. However, in order to confirm the color tones of an output image in a color copying machine, a full-color display preview system is preferable.
On the other hand, in a digital color copying machine, a requirement for high-speed processing is strong, and in order to meet this requirement, a digital color copying machine which comprises four photosensitive drums and Y, M, C, and K developers in correspondence with these drums, has been proposed. In such machine, an image memory for compensating for spatial offsets between adjacent photosensitive drums is indispensable, and in order to realize higher-grade image processing, a full-page image memory is preferably arranged.
However, the above-mentioned prior art suffers the following problems. That is, when image data stored in the full-page image memory is subjected to processing equivalent to image processing of the copying machine main body in a software manner, and the processed data is displayed on a color monitor, a preview system can be constituted without largely modifying the hardware arrangement. However, when the copying machine main body has a large number of complex edit functions, the scale of a software program for the preview image processing increases, and its calculation amount also increases. In order to shorten the time required for forming a preview image, a high-speed hardware arrangement must be adopted, resulting in an increase in cost.